using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var n = NN;
        var a = NList;

        var leftup = new int[n];
        var tmp = Enumerable.Repeat(1_000_000_007, n).ToArray();
        for (var i = 0; i < n; ++i)
        {
            var pos = LowerBound(0, a[i], tmp);
            leftup[i] = pos;
            tmp[pos] = a[i];
        }
        var rightup = new int[n];
        for (var i = 0; i < n; ++i) tmp[i] = 1_000_000_007;
        for (var i = n - 1; i >= 0; --i)
        {
            var pos = LowerBound(0, a[i], tmp);
            rightup[i] = pos;
            tmp[pos] = a[i];
        }
        var leftdown = new int[n];
        for (var i = 0; i < n; ++i) tmp[i] = 0;
        for (var i = 0; i < n; ++i)
        {
            var pos = LowerBound(0, -a[i], tmp);
            leftdown[i] = pos;
            tmp[pos] = -a[i];
        }
        var rightdown = new int[n];
        for (var i = 0; i < n; ++i) tmp[i] = 0;
        for (var i = n - 1; i >= 0; --i)
        {
            var pos = LowerBound(0, -a[i], tmp);
            rightdown[i] = pos;
            tmp[pos] = -a[i];
        }
        var ans = 0;
        for (var i = 0; i < n; ++i) ans = Math.Max(ans, Math.Max(Math.Min(leftup[i], rightup[i]), Math.Min(leftdown[i], rightdown[i])));
        WriteLine(ans);
    }
    static int LowerBound(int left, int min, IList<int> list)
    {
        if (list[left] >= min) return left;
        var ng = left;
        var ok = list.Count;
        while (ok - ng > 1)
        {
            var center = (ng + ok) / 2;
            if (list[center] < min) ng = center;
            else ok = center;
        }
        return ok;
    }
}